Hierarchically porous carbonized Pleurotus eryngii based solar steam generator for efficient wastewater purification

Solar steam generation has been considered as an effective strategy to alleviate freshwater shortage. Interfacial solar steam generation utilizing biomass materials as the core of evaporator has shown great potential to overcome the freshwater crisis based on its distinctive natural structure. Herein, we reported a sustainable, efficient and convenient biomass solar evaporator using carbonized Pleurotus eryngii (C-PE). Benefiting from the microporous carbon skeleton and microchannels cooperatively work, the as-prepared device exhibited the integrated functions of excellent photothermal conversion and rapid evaporation. The hierarchically porous structure of C-PE could entice interior multiple light reflection to enable all-directional light absorption (>92.1%) and enhance the capability of photothermal conversion. This device showed a high evaporation rate of 1.22 kg m−2 h−1 under a power density of 1 kW m−2. Moreover, the high efficiencies of 81.7% under 1 kW m−2 power density and 95.1% under 4 kW m−2 power density for C-PE evaporator were achieved. Furthermore, C-PE was used to extract potable condensate from wastewater samples containing Na+, heavy metal ions, dyes, and oil. With the advantages of low-cost, abundant and long-term stability, C-PE evaporator showed great application potential in clean water production, which can be used for future bio-derived solar thermal material.